Phosphorated oils



PHOSPHORATED OHS Thomas W. Findley, La Grange, Ill., assignor to Swift & Company, Chicago, 11]., a corporation of Illinois No Drawing. Filed June 4, 1956, Ser. No. 595,559 8 Claims. (Cl. 260403) This invention in general relates to phosphorated oils and to processes for este'rifying animal, marine, and vegetable oils with phosphorus acids.

Sulfated oils are comparatively easily prepared by simply reacting concentrated sulfuric acid with unsaturated oils. Unlike sulfated oils, phosphated oils are more diflicult to prepare and are not made by simply reacting phosphoric acid directly with an unsaturated oil. One known method for preparing phosphated triglycerides is the reaction of phosphoric anhydride with castor oil, which contains a substantial portion of ricinoleic acid, the monohydroxy group of said acid being esterified by the phosphoric anhydride. This process is limited to one fatty oil and to one phosphorated triglyceride composition as the end product with the phosphate ester always in the 12 position.

The process of this invention on the other hand involves the reaction of epoxidized fatty oils with polybasic phosphorus acids to produce phosphorated oils. One method for preparation of phosphorated oils involves the use of a mutual solvent, where required, for the phosphorus acids and the epoxidized oil. Solvents which have been found effective are tetrahydrofuran, dimethyl ether, dioxane, acetone, and alkanols such as ethanol. The phosphorus acids are dissolved in the solvent, and the epoxidized oil is then added to the solution slowly and with good stirring. In cases where the acid is dispersible or soluble in the epoxidized oil, as is the case with monoalkyl phosphoric acids such as mono-propyl and monobutyl phosphoric acids, the acid and oil can be mixed directly. The addition of the epoxidized oil is controlled so that the heat of the reaction does not cause the solvent to boil off. After all of the epoxidized oil is added, the solvent is boiled off by heating the reactants and products. The hydroxylated phosphorated triglyceride is recovered as an un-neutralized, viscous oil and is water washed to remove excess phosphorus acid. The water soluble alkali metal salt may be formed by neutralization of the oil with alkali.

The invention herein described is intended to include within its scope fatty oils containing fatty acyl radicals of carbon chain length of to 22 carbons and having phosphorus acid groups on at least one acyl radical, in which at least one acid hydrogen of the phosphorus acid group is free to form a salt, and the carbon contiguous to the carbon to which the phosphorus acid group is attached contains a hydroxyl group. The method described herein is applicable to epoxy fatty acids, epoxy fatty alcohols or epoxy fatty esters as one of the reactants. The esters may be composed of monohydric alcohols such as methyl, ethyl, butyl alcohols, etc., or a polyhydric alcohol such as glycol and glycerol in which one or more of the fatty acyl radicals contain the phosphorated group. Fatty triglycerides obtained from natural sources which have application in the instant invention as the base material include tallow, grease, menhaden oil, soybean oil,

Patented Dec. 20, 1960 linseed oil, etc. Also included is the complex mixture in sperm oil, which contains in addition to triglycerides, esters of long chain fatty acids and long chain fatty alcohols.

The phosphorus acids are polybasic acids and thus have, after esterification with the epoxidized oils, a reactive acid group. They include orthophosphoric, pyrophosphoric, thiophosphoric, tetraphosphoric, phosphorous, mono alkyl and mono aryl phosphoric and phosphonic acids. Thus the compositions of this invention are fatty acids and organic esters and salts thereof wherein at least one fatty acyl radical contains a hydroxyl and phosphorus acid ester group on contiguous carbons. The acyl radical would be characterized by the following grouping:

wherein X is from the group S and O and Z is -H, -OH, OP=O(OH) [-OP=O(OH)] OH; alkyloxy, aryloxy, alkyl, or aryl. Thus, the phosphorated oils contain a reactive hydrogen free to react with basic compositions such as the alkali metal hydroxides, alkaline earth metal hydroxides or oxides, or heavier metal hydroxides or oxides, ammonia, and simple amines such as methyl amine, butyl amine, trimethyl amine and mono-, dior triethanolamines or morpholine.

Another method of preparation of phosphorated oils is the reaction of an epoxidized triglyceride oil having an average epoxy equivalency of more than 1.33 epoxide groups per molecule with the polybasic phosphorus acid in substantially equivalent amounts. When the reactants are mixed rapidly, the mixture war-ms up spontaneously and solidifies. When the solid mixture is held at elevated temperatures for several days or allowed to set at room temperature for several months, a liquid product is obtained. This liquid product which is insoluble in water gives a completely water soluble product upon neutralization with alkali to a pH of about 7. This solution can be dried to give the solid alkali phosphorated product which may be redissolved in water if desired at a later date. The aqueous solutions have considerable surface activity.

While I do not intend to be limited thereby, it is my theory that the initial solid product in the above reaction is a polymer obtained through the reaction of the polybasic phosphorus acid and the epoxide. This product comprises alternating molecules of the oil and the polybasic acid. When the product stands for several months at room temperature or is held for several days at elevated temperatures, it is my belief that the polymer rearranges and/or hydrolyzes to a mono-phosphorated oil.

The product produced by the method first described wherein a mutual solvent was usually employed contains essentially one phosphorus acid group per epoxide group in the original oil. On the other hand, the product resulting from polymerization and hydrolysis is essentially a triglyceride containing about one phosphorus acid group per glyceride molecule. Hydrolysis of the polymer leaves di-hydroxy fatty acyl radicals on other of the glyceride acyl radicals. Taking tri-olein, for purposes of illustration of the mechanism of the reaction, epoxidation thereof produces essentially glyceryl tri-(9,l0 epoxy) stearate. The reaction of glyceryl tri-(9,10 epoxy) stearate with orthophosphoric acid produces a polymer of the following 3 4 configuration through esterification of the phosphoric acid stirring. The ether is boiled off, and 40% sodium hyand the epoxy triglyceride. droxide is added to bring the pH to about 7.0. The product containing about 21% water weighs about 153 II grams. Upon cooling to room temperature, the product O P O 5 is a solid. The solid product dissolves in a small amount E0 of water to give a clear solution. When a large amount if of water is used, however, a cloudy solution is obtained. 03 0 P 0 011 It is quite soluble in mineral oil, particularly when a small I l l l l amount of additional water is added. This phosphated I tallow is a good emulsifying agent for water-oil systems.

Example III I One hundred grams of methyl 9,10 epoxy stearate H6 0 O (3.8% oxirane oxygen) is slowly added to a solution of I 27.7 grams of 85% phosphoric acid in 50 ml. of ether. Sodium hydroxide is then added to bring the pH to I about 7. The liquid product, the sodium salt of methylhydroxy, phosphato-stearate, was surface active in a mancogfipgolnalgclllrolysis, the product w1ll have the following nerjimilar to the Product of Example IL Example IV One gram-mol of 85 orthophosphoric acid is dissolved in 500 cc. of tetrahydrofuran. The solution is heated to boiling; heat is removed; and 400 grams of epoxidized sperm oil (4.0% oxirane oxygen) is added dropwise at a slow rate. There is continued boiling due to the exothermic nature of the reaction. After all the epoxidized sperm oil is added, the solvent is distilled off. The product, a viscous oil, is neutralized to pH 7 with alkali. Upon or the less hydrolyzed form, drying, a neutral, water soluble solid having surface-ac- HO 0 tive properties is obtained.

Example V To 15.4 grams of monobutyl phosphoric acid is added slowly 26.7 grams of epoxidized soybean oil (60% oxiirane oxygen). The exothermic reaction is complete in a OH OH few minutes after all of the oil is added. The mixture I I is held on a steam bath for one hour. The resulting viscous liquid is rendered water soluble by neutralization with 15 grams of triethanolamine.

The mono-aryl phosphoric acid and other homologous mono-alkyl phosphoric acid esters of the oils are prepared in a similar manner by reacting, for example, monocresyl E l 1 orthgmollogous alkylhpholspltilorichacids beweenhethyl and 00 a ecy or monop eny p osp one am w1t an epox- 388 grams of 85% phosp orlc 801d dlssolved m idized oil. The same is true for phosphonic acids such h ter of absolute ether. One thousand grams of epoxias phfinyl phosphonic acid d zed soybean 011 9 oxlrane 9 1S the Obviously, many modifications and variations of the insolunon slowly and wlth good I Addmon is slow vention as hereinbefore set forth may be made without g Pi the :F of i g does not cause the departing from the spirit and scope thereof, and therefore e 0 01 i oward t 6 en the a t only such limitations should be imposed as are indicated addition of 011 is even slower than 1t.1s at the beginning to hold down the foam of the now viscous product. After m i gfi claimsall of the epoxidized oil is added, the product is placed 1' A niethod which Comprises t ifyin f a poly gi lcig g i l P l 1 exce? ethef g a figg basic phosphorus acid and an epoxy triglyceride oil havphospgoric 2 125 H e m wa mmera an 0 ing an average epoxy equivalency more than 1.33 epoxide The hos hat-ed oil is then I d th 07 groups per molecule to obtain a solid product and holding 80cm Ph dP d 1 e W1 0 aqueous said product at temperatures above room temperature to 1 m Y 511 Clem to s the PH to obtain a liquid product having about one phosphorus acid about 7, and additional water is added to bring the total ester group per molecule. water content in the product to about 50%. This prod- A method which comprises reacting a polybasic k wfr lg ri g ifia roifil l fg 0%:5322? E 2? ig phosphorus acid and an epoxidized fatty oil having acyl p m r re radlcals of a carbon chain length of 10-22 carbons and action using dioxane as the solvent, the results obtained an expoxy content above about 2% i oxygen in a are similar with the exception that a higher temperature Solvent medium to produce a phosphorus acid ester of is necessary to boil off the dioxane, and some darkening Said fatty 1 of 1th; plrl z tguizltorizutzbtalrrledi1 h d t h n h 3. A method which comprises esterification in a mutual add It P PY P p P an elrap OPP of solvent of an epoxidized triglyceride oil having an oxirane 1 es ers are prepared by a similar procedure. The content above about 2% oxirane oxygen d a polybasic sodium salts are emulsifiers for 011 and water systems. phosphorus id h b t least one of the fatty acyl Example H radicals of said triglyceride is esterified with said phosphorus acid and the carbon ad acent the phosphorus acid To a solution of 18.8 grams of phosphoric acid in group is substituted with a hydroxyl group. 50 ml. of ether is added grams of epoxidized tallow 4. The method of claim 3 wherein the epoxidized tri- (-2% oxirane oxygen) at a slow rate and with vigorous ;,glyceride oil is epoxidized sperm oil.

The following examples are provided to facilitate fur- 40 ther understanding of the present invention and should not as such be construed as placing any limitation on the invention as defined in the appended claims.

References Cited in the file of this patent UNITED STATES PATENTS Dickey et a1. Apr. 4, 1944 McNalley et a1 Oct. 9, 1945 Dickey et a1 Apr. 5, 1949 Dickey et a1 Dec. 6, 1949 Cupery Nov. 15, 1955 Fang Aug. 26, 1958 

2. A METHOD WHICH COMPRISES REACTING A POLYBASIC PHOSPHORUS ACID AND AN EPOXIDIZED FATTY OIL HAVING ACYL RADICALS OF A CARBON CHAIN LENGTH OF 10-22 CARBONS AND AND EXPOXY CONTENT ABOVE ABOUT 2% OXIRANE OXYGEN IN A SOLVENT MEDIUM TO PRODUCE A PHOSPHORUS ACID ESTER OF SAID FATTY OILS. 